Cullen Insulation is a local insulation installer, building science expert and energy performance consultant. We built our business on the simple, honest qualities that add up to total customer satisfaction. Cullen Insulation started in 1988 with $700 to buy a used pick-up truck. Through skillfulness, attention to detail, and pride in workmanship, we have expanded to five locations, more than 60 team members, and over 40 vehicles. Our offerings now include fiberglass insulation, spray foam, rigid foam insulation, waterproofing and air barrier installation—and we service both commercial and residential projects.With locations in Fargo-Moorhead, Grand Forks, Bismarck, Sioux Falls, and Bozeman, we can be where you need when you need us.

Over the years, we’ve become known as a leader in our market, and we’ve received national recognition for our exceptional insulation practices by the Owens Corning® Certified Energy Expert® program. However, our growth has not shifted our foundation. First and foremost, we maintain a commitment to excellence and a pledge to do simply the best job on time, every time.

Why Choose a Local Owens Corning® Certified Energy Expert® Professional?

By selecting Cullen Insulation, you get the peace of mind that comes from knowing your insulation contractor has been certified by Owens Corning. What does that mean for you?

  • We’re trained to optimize comfort. We’re energy consultants with extensive training and hands-on experience.
  • We’re tested for proven performance. We are regularly tested and assessed to ensure Grade 1 installation quality.
  • We’re backed by a trusted leader. We are able to offer a limited lifetime warranty on qualifying Owens Corning® fiberglass products and an exclusive limited lifetime warranty on workmanship.*

View our Service Area to learn more about our multi-state reach. And, if you are interested in joining our team, check out our Employment Page.

*See actual warranty for complete details, limitations and requirements. For the lifetime of the Home beginning from date of installation by an Owens Corning® Certified Energy Expert®.


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